The Walking-Off-Weight Breakthrough

At high speeds, walking burns even more calories than running. Here’s how to boost your pace (trust us, it’s easier than you think)

by Michele Stanten

Photograph: Illustrated by Eduardo Recife

Karen Liptrap loved to walk, but when she wanted to lose weight, she chose the same exercise that many other women do: running. A year later, though, she developed significant pain and swelling in her right knee and had to wear a brace for several months. That’s when she saw an advertisement for a walking coach who promised to teach clients “how to power walk a marathon.”

When Liptrap signed up for the program, she was fitness walking at 3.7 miles per hour. “I thought that was a pretty good clip,” recalls the 47-year-old Oakville, Ontario, resident. But her opinion, and her speed, were about to change radically. Two months into the training, she walked her first half-marathon averaging 4.4 mph. Today, Liptrap averages 5 mph (a 12-minute mile) for her daily walks.

Up to SpeedWalking is often pigeonholed as a low- to moderate-intensity workout. And for good reason: Even those who make a real effort rarely get their internal speedometer above 4 mph. But that doesn’t have to be the case. If you can improve your game by only a few tenths of a mile (click here to see our three-step program for technique-tweaking tips), walking can become an intense calorie-torching exercise. According to a 2006 study in the British Journal of Sports Medicine, walkers in their fifties burn 32 percent more calories when they adjust their speed from 4.1 to 4.6 mph compared with only a 25 percent boost from 3.6 to 4.1 mph.

The crucial dividing line is 4 mph. “Moving from 4 to 4.2 mph increases calorie expenditure more than changing from 3.8 to 4 miles, and going from 4.2 to 4.4 burns even more calories for the increment,” explains walking expert Mark Fenton, author of The Complete Guide to Walking for Health, Weight Loss, and Fitness. “Anything you get above 4 mph is going to be a big win, and it’s a bigger win for each additional tenth you can add.”

There’s a different dividing line at 5 mph. Once you exceed that speed, your calorie burn becomes greater than it would be if you were running. That’s because at about this pace, running starts becoming lessphysiologically demanding than walking. “The mechanics of the two tasks are completely different,” explains Peter Adamczyk, PhD, a biomechanics researcher in Ann Arbor, Michigan. “When you walk, muscles have to generate energy for every step. In running, you’re temporarily airborne, and you fall onto your leg, which acts like a spring.” It’s similar to the difference between throwing a ball up in the air over and over again (walking) and bouncing a ball (running). You use more muscles and energy to throw a ball than you do to bounce it. And even at speeds above 4 or 5 mph, walking is much easier on the joints than running is.
But are youcapable of walking 4.5, 5 or even 6 mph? Absolutely, and you don’t have to be especially fit to do it. Over the past decade, Lee Scott, the walking coach who helped Liptrap speed up, has trained more than 1,200 walkers—many of them inactive, overweight women in their thirties, forties and fifties—to go faster. After four weeks of coaching and dedicated training, many are able to shave a minute off their one-mile walk time; some end up covering a mile at speeds up to 6.2 mph. With persistence, almost anyone can learn to reach speeds above 5 mph, says Scott, but women who are free of joint problems and have been athletic in the past tend to pick up the techniques faster. “You need to have good messaging from your brain to your muscles, and it’s my experience that people who played sports when they were younger tend to have a better messaging system,” says Scott.